Whereas rotors for continuous mixers were previously employed as one piece with their drive and driven journals, recently three-piece rotor construction has been developed for such mixers. Such three-piece rotor construction is disclosed for example in U.S. Pat. No. 5,180,225, issued Jan. 19, 1993 to J. R. Piccolo et al. The apparatus disclosed in said patent comprises a rotor body connected to discrete drive and driven journals. The many advantages of such three-piece rotor construction are evident, particularly that concerning the ease of detaching and removing the rotor bodies from the mixing chamber in which they are housed without necessity for removing the journals from the journal housings or otherwise disturbing journal bearings. This advantage significantly reduces the maintenance and downtime of mixers for cleaning rotors and mixing chambers or for changing rotor types or worn out rotors or replacing oil or polymer seals. In the aforesaid U.S. Pat. No. 5,180,225, quick coupling/disconnect means is disclosed for achieving coupling of the rotor body with the journals in proper co-axial alignment. The coupling/disconnect means in said patent employs concentricity and piloting means along with threaded collar retainers. One drawback of such coupling means resides in the fact that significant spacing between the rotor and journal housing is required to permit assembly and coupling of said coupling elements. Therefore, the quick connect/disconnect coupling elements of said patent cannot be employed in situations where the spacing between the rotor and journal housing are very limited.
Thus, it is highly desirable that a three-piece rotor construction be available wherein the coupling means employed does not require any significant spacing between the rotor body and the journal bodies in order to situate and connect the coupling means while still being able to attain the desired common axial alignment of the axis of rotation of the rotor and the journals. In addition, it would be most desirable to provide a quick connect/disconnect coupling means providing the aforesaid axial alignment whereby a one piece rotor may be easily and conveniently converted to three-piece rotor construction.